Protection circuit for input and output ports of unmanned aerial vehicle

Abstract

The utility model discloses a protection circuit for an input / output port of an unmanned aerial vehicle, and relates to the technical field of unmanned aerial vehicle protection circuits. The circuit specifically comprises a solid-state relay U2, a comparison circuit, a power supply VCC1 and a resistor R1. The controlled end of the solid-state relay U2 is connected between the output end of the unmanned aerial vehicle micro-control unit and the input end of a controlled unit, the power supply VCC1 is connected to the first end of the resistor R1, the second end of the resistor R1 is connected to the anode of a light-emitting diode of the solid-state relay U2, the comparison circuit is connected to the cathode of the light-emitting diode of the solid-state relay U2, and the output end of the solid-state relay U2 is connected to the output end of the unmanned aerial vehicle micro-control unit. The comparison circuit is used for detecting the voltage value of the controlled unit, and when the voltage value of the controlled unit exceeds a preset voltage value, high electric frequency is output to enable a light-emitting diode of the solid-state relay U2 to be kept in an off state, so that the controlled end of the solid-state relay U2 is disconnected. The utility model aims to realize overvoltage protection of input and output ports of the unmanned aerial vehicle.

Description

Technical Field

[0001] The utility model relates to the technical field of UAV protection circuits, and particularly relates to a protection circuit for the input and output ports of a UAV. Background Art

[0002] With the continuous development of UAV technology and the increasing expansion of application fields, plant protection UAVs have become one of the indispensable important tools in modern agriculture. Plant protection UAVs are mainly used for operations such as pesticide spraying, sowing, and monitoring. Their characteristics of high efficiency, precision, and environmental protection have significantly improved the efficiency and effectiveness of agricultural production. However, with the improvement of UAV performance, the complexity of its internal system and the working voltage are also increasing. For example, modern plant protection UAVs usually use power batteries, and the voltage can reach 60V or even higher. While providing strong power to the UAV, this also poses higher requirements for the safety of the internal electronic system.

[0003] In the plant protection UAV system, the flight control system (Flight Control System, FCS) is one of the core components, which is responsible for the attitude control, path planning, and task execution of the UAV. The flight control system is usually controlled by a microcontroller unit (Microcontroller Unit, MCU), and the MCU communicates with external sensors, actuators, and other components through its input / output (Input / Output, IO) ports.

[0004] However, in the prior art, the signal ports of the MCU are often not equipped with effective protection circuits. The working environment of plant protection UAVs is complex and changeable, and factors such as electromagnetic interference, electrostatic discharge, and high-voltage electric shock may cause overvoltage impacts on the IO ports of the flight control system. Once the IO port of the MCU is short-circuited with a high-voltage power source (such as the positive pole of the battery), the IO port will be burned out due to excessive voltage and current, and even the entire MCU may be damaged, resulting in the failure of the flight control system and seriously affecting the normal operation and operation safety of the UAV.

[0005] Therefore, how to achieve overvoltage protection for the input and output ports of UAVs has become an urgent technical problem to be solved. Summary of the Utility Model

[0006] The main purpose of the utility model is to provide a protection circuit for the input and output ports of a UAV, aiming to achieve overvoltage protection for the input and output ports of the UAV.

[0007] To achieve the above purpose, the utility model proposes a protection circuit for the input and output ports of a UAV, including: a solid-state relay U2, a comparison circuit, a power supply VCC1, and a resistor R1;

[0008] The controlled terminal of the solid-state relay U2 is connected between the output terminal of the UAV micro-control unit and the input terminal of the controlled unit. The power supply VCC1 is connected to the first end of the resistor R1. The second end of the resistor R1 is connected to the anode of the light-emitting diode of the solid-state relay U2. The comparison circuit is connected to the cathode of the light-emitting diode of the solid-state relay U2. The comparison circuit is used to detect the voltage value of the controlled unit. When the voltage value of the controlled unit exceeds the preset voltage value, a high level is output to keep the light-emitting diode of the solid-state relay U2 off, so that the controlled terminal of the solid-state relay U2 is disconnected.

[0009] In an embodiment of the present application, the comparison circuit includes:

[0010] Comparator U1. The non-inverting input terminal of the comparator U1 is connected to the voltage-dividing circuit to obtain the voltage of the controlled unit. The inverting input terminal of the comparator U1 is connected to the reference circuit to obtain the preset voltage value.

[0011] In an embodiment of the present application, the voltage-dividing circuit includes:

[0012] Resistors R2 and R3. Wherein, the first end of the resistor R2 is connected to the controlled unit. The second end of the resistor R2 is connected to the first end of the resistor R3. The second end of the resistor R3 is grounded. The non-inverting input terminal of the comparator U1 is connected between the second end of the resistor R2 and the first end of the resistor R3.

[0013] In an embodiment of the present application, the reference circuit includes:

[0014] Power supply VCC2, resistor R4, resistor R5. Wherein, the power supply VCC2 is connected to the first end of the resistor R4. The second end of the resistor R4 is connected to the first end of the resistor R5. The second end of the resistor R5 is grounded. The inverting input terminal of the comparator U1 is connected between the second end of the resistor R4 and the first end of the resistor R5.

[0015] In an embodiment of the present application, the comparison circuit further includes:

[0016] Power supply VCC3 is connected to the comparator U1 to provide a working voltage for the comparator U1.

[0017] In an embodiment of the present application, the comparison circuit further includes:

[0018] Capacitor C1. The first end of the capacitor C1 is connected between the power supply VCC3 and the comparator U1. The second end of the capacitor C1 is grounded.

[0019] In an embodiment of the present application, the power supplies VCC1, VCC2, and VCC3 are the same power supply.

[0020] With the above technical solution, the solid-state relay has an extremely fast switching speed, can quickly respond to the signals of the comparison circuit, and quickly cut off or resume signal transmission. The comparison circuit can monitor the voltage value of the controlled unit in real time, and immediately output a high level when the voltage exceeds the preset value, ensuring that the output end of the UAV micro-control unit can be quickly protected during overvoltage. The resistor R1 limits the current flowing through the light-emitting diode of the solid-state relay, preventing the current from being too large and damaging the light-emitting diode, and enhancing the reliability of the circuit. Brief Description of the Drawings

[0021] The present invention will be described in detail below in conjunction with specific embodiments and the accompanying drawings, where:

[0022] Figure 1 is a schematic structural diagram of the first embodiment of the present invention. Detailed Embodiments

[0023] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and do not constitute a limitation to the present invention.

[0024] As Figure 1 shown, in order to achieve the above objective, the present invention provides a protection circuit for the input and output ports of a UAV, including: a solid-state relay U2, a comparison circuit, a power supply VCC1, and a resistor R1;

[0025] The controlled end of the solid-state relay U2 is connected between the output end of the UAV micro-control unit and the input end of the controlled unit. The power supply VCC1 is connected to the first end of the resistor R1. The second end of the resistor R1 is connected to the anode of the light-emitting diode of the solid-state relay U2. The comparison circuit is connected to the cathode of the light-emitting diode of the solid-state relay U2. The comparison circuit is used to detect the voltage value of the controlled unit. When the voltage value of the controlled unit exceeds the preset voltage value, a high level is output to keep the light-emitting diode of the solid-state relay U2 off, so that the controlled end of the solid-state relay U2 is disconnected.

[0026] Specifically, the controlled terminal of the solid-state relay U2 is connected between the output terminal of the UAV microcontroller unit and the input terminal of the controlled unit, and determines the on / off of the control signal according to the state of the light-emitting diode. The anode of the light-emitting diode is connected to the power supply, and the current is limited by the resistor R1. The cathode of the light-emitting diode is connected to the comparison circuit for receiving the output signal of the comparison circuit. The comparison circuit is used to detect the voltage value of the controlled unit and compare it with the preset voltage value. When the detected voltage value exceeds the preset voltage value, a high-level signal is output. When the detected voltage value does not exceed the preset voltage value, a low-level signal is output. The power supply VCC1 provides voltage to the resistor R1 and the light-emitting diode of the solid-state relay U2. The resistor R1 is connected between the power supply VCC1 and the anode of the light-emitting diode of the solid-state relay U2, playing a role in current limiting and protection.

[0027] Adopting the above technical solution, the solid-state relay has an extremely fast switching speed, can quickly respond to the signal of the comparison circuit, and quickly cut off or restore signal transmission. The comparison circuit can real-time monitor the voltage value of the controlled unit, and immediately output a high level when the voltage exceeds the preset value, ensuring that the output terminal of the UAV microcontroller unit can be quickly protected during overvoltage. The resistor R1 limits the current flowing through the light-emitting diode of the solid-state relay, preventing the light-emitting diode from being damaged by excessive current and enhancing the reliability of the circuit.

[0028] In an embodiment of the present application, the comparison circuit includes:

[0029] A comparator U1, the non-inverting input terminal of the comparator U1 is connected to the voltage dividing circuit for obtaining the voltage of the controlled unit; the inverting input terminal of the comparator U1 is connected to the reference circuit for obtaining the preset voltage value.

[0030] Specifically, the non-inverting input terminal of the comparator U1 is connected to the voltage dividing circuit for obtaining the voltage of the controlled unit. The inverting input terminal is connected to the reference circuit for obtaining the preset voltage value. Among them, the voltage dividing circuit is composed of multiple resistors for reducing the voltage of the controlled unit to the range that the comparator can process. The voltage signal provided to the non-inverting input terminal of the comparator U1. The reference circuit is composed of a voltage stabilizer and a resistor voltage divider for generating a stable preset voltage value. The voltage signal provided to the inverting input terminal of the comparator U1.

[0031] Its working principle is:

[0032] The voltage of the controlled unit is stepped down by the voltage dividing circuit and then input to the non-inverting input terminal of the comparator U1. The voltage dividing circuit ensures that the voltage signal input to the comparator is within its working range.

[0033] The reference circuit generates a stable preset voltage value and inputs it to the inverting input terminal of the comparator U1.

[0034] The reference voltage is used to compare with the voltage of the controlled unit to ensure the accuracy and reliability of the threshold of the protection circuit.

[0035] Comparator U1 compares the voltages at the non-inverting input terminal and the inverting input terminal in real time.

[0036] When the voltage at the non-inverting input terminal (i.e., the voltage of the controlled unit) is lower than the reference voltage at the inverting input terminal, the comparator outputs a low-level signal.

[0037] When the voltage at the non-inverting input terminal is higher than the reference voltage at the inverting input terminal, the comparator outputs a high-level signal.

[0038] The output terminal of comparator U1 is connected to the cathode of the light-emitting diode (LED) of solid-state relay U2. When the comparator outputs a low level, the light-emitting diode conducts, and the controlled terminal of the solid-state relay conducts, allowing the signal to be transmitted. When the comparator outputs a high level, the light-emitting diode goes out, and the controlled terminal of the solid-state relay disconnects, cutting off the signal transmission.

[0039] Adopting the above technical solution, the comparison circuit compares the voltage of the controlled unit with the reference voltage to achieve accurate overvoltage detection and protection. Ensure that in the case of overvoltage, solid-state relay U2 quickly disconnects to protect the microcontroller unit and the controlled unit. The reference circuit provides a stable preset voltage to ensure that comparator U1 can reliably detect overvoltage conditions. The voltage division circuit ensures that the voltage input to the comparator is within a reasonable range, improving the reliability of the system. Comparator U1 has fast voltage comparison ability and can quickly respond to voltage changes. Combining with the fast switching characteristics of the solid-state relay, fast overvoltage protection of the system is achieved.

[0040] In an embodiment of the present application, the voltage division circuit includes:

[0041] Resistor R2 and resistor R3; wherein, the first end of resistor R2 is connected to the controlled unit, the second end of resistor R2 is connected to the first end of resistor R3, the second end of resistor R3 is grounded, and the non-inverting input terminal of comparator U1 is connected between the second end of resistor R2 and the first end of resistor R3.

[0042] Specifically, the first end of resistor R2 is connected to the voltage output terminal of the controlled unit to obtain the voltage of the controlled unit. The second end of resistor R2 is connected to the first end of resistor R3 and also to the non-inverting input terminal of comparator U1.

[0043] The first end of resistor R3 is connected to the second end of resistor R2. The second end of resistor R3 is grounded to complete voltage division. The connection point between the second end of resistor R2 and the first end of resistor R3 obtains the voltage signal after voltage division.

[0044] With the above technical solution, through the voltage division of resistor R2 and resistor R3, the voltage of the controlled unit is accurately divided to a range suitable for the comparator U1 to process. The voltage signal after voltage division can accurately reflect the actual voltage of the controlled unit, improving the accuracy of voltage detection. The voltage of the controlled unit may be relatively high, and directly inputting it to the comparator U1 may exceed its working range and cause damage. By dividing the voltage with resistor R2 and resistor R3, the voltage can be reduced to a safe range to protect the comparator U1 from high voltage damage.

[0045] In an embodiment of the present application, the reference circuit includes:

[0046] Power supply VCC2, resistor R4, resistor R5; wherein, the power supply VCC2 is connected to the first end of the resistor R4, the second end of the resistor R4 is connected to the first end of the resistor R5, the second end of the resistor R5 is grounded, and the inverting input terminal of the comparator U1 is connected between the second end of the resistor R4 and the first end of the resistor R5.

[0047] Specifically, the power supply VCC2 is connected to the first end of the resistor R4 to provide a stable voltage source for the reference circuit. The first end of the resistor R4 is connected to the power supply VCC2. The second end of the resistor R4 is connected to the first end of the resistor R5 and also to the inverting input terminal of the comparator U1. The first end of the resistor R5: is connected to the second end of the resistor R4. The second end of the resistor R5 is grounded to form a part of the voltage division circuit. It is connected between the second end of the resistor R4 and the first end of the resistor R5 to obtain the reference voltage signal.

[0048] With the above technical solution, by providing a stable voltage source through the power supply VCC2, the resistor R4 and the resistor R5 form a stable voltage division circuit to ensure that the inverting input terminal of the comparator U1 obtains a stable reference voltage. The stable reference voltage makes the voltage comparison process more reliable and avoids misjudgment caused by the fluctuation of the reference voltage. The voltage division ratio of the resistor R4 and the resistor R5 can be adjusted as needed to accurately set the reference voltage value. So that the comparator U1 can accurately compare the voltage of the controlled unit with the preset reference voltage to achieve precise overvoltage protection.

[0049] In an embodiment of the present application, the comparison circuit further includes:

[0050] The power supply VCC3 is connected to the comparator U1 to provide a working voltage for the comparator U1.

[0051] With the above technical solution, the power supply VCC3 supplies power to the comparator U1 to ensure the stable operation of the comparator U1.

[0052] In an embodiment of the present application, the comparison circuit further includes:

[0053] A capacitor C1, a first end of the capacitor C1 is connected between a power supply VCC3 and a comparator U1, and a second end of the capacitor C1 is grounded.

[0054] With the above technical solution, the power supply VCC3 is filtered by the capacitor C1 to provide a more reliable power supply and extend the service life of the device.

[0055] In an embodiment of the present application, the power supply VCC1, the power supply VCC2, and the power supply VCC3 are the same power supply.

[0056] With the above technical solution, the circuit structure can be simplified and the circuit design is facilitated.

[0057] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the inventive concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A protection circuit for an input and output port of a drone, characterized in that: include: Solid-state relay U2, comparison circuit, power supply VCC1, and resistor R1; The controlled end of the solid-state relay U2 is connected between the output end of the drone microcontroller unit and the input end of the controlled unit, the power supply VCC1 is connected to the first end of the resistor R1, the second end of the resistor R1 is connected to the anode of the light-emitting diode of the solid-state relay U2, and the comparison circuit is connected to the cathode of the light-emitting diode of the solid-state relay U2. The comparison circuit is used to detect the voltage value of the controlled unit. When the voltage value of the controlled unit exceeds the preset voltage value, a high electrical frequency is output to keep the light-emitting diode of the solid-state relay U2 in an off state, so that the controlled end of the solid-state relay U2 is disconnected.

2. The protection circuit for the input and output port of a drone as claimed in claim 1, characterized in that: The comparison circuit comprises: A comparator U1, wherein the same-direction input terminal of the comparator U1 is connected to a voltage-dividing circuit for obtaining the voltage of the controlled unit; and the reverse input terminal of the comparator U1 is connected to a reference circuit for obtaining a preset voltage value.

3. The protection circuit for the input and output port of a drone as claimed in claim 2, characterized in that: The voltage divider circuit comprises: Resistor R2, resistor R3; wherein the first end of resistor R2 is connected to the controlled unit, the second end of resistor R2 is connected to the first end of resistor R3, the second end of resistor R3 is grounded, and the same-direction input end of comparator U1 is connected between the second end of resistor R2 and the first end of resistor R3.

4. The protection circuit for the input and output port of a drone as claimed in claim 2, characterized in that: The reference circuit comprises: Power supply VCC2, resistor R4, resistor R5; wherein, power supply VCC2 is connected to the first end of resistor R4, the second end of resistor R4 is connected to the first end of resistor R5, the second end of resistor R5 is grounded, and the inverting input end of comparator U1 is connected between the second end of resistor R4 and the first end of resistor R5.

5. The protection circuit for the input and output port of a drone as claimed in claim 4, characterized in that: The comparison circuit further comprises: The power supply VCC3 is connected to the comparator U1 and is used to provide a working voltage for the comparator U1.

6. The protection circuit for the input and output port of a drone as claimed in claim 5, characterized in that: The comparison circuit further comprises: Capacitor C1, a first end of the capacitor C1 is connected between the power supply VCC3 and the comparator U1, and a second end of the capacitor C1 is grounded.

7. The protection circuit for the input and output port of a drone as claimed in claim 5, characterized in that: The power source VCC1 , the power source VCC2 , and the power source VCC3 are the same power source.

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